ARCH 316 Lecture 3: ARCH315MechnicalSystems
Document Summary
3/29 introduction to hvac (heating, ventilation, air conditioning) Airflow (measured in cfm cubic feet per minute) 1 ton = 12000 btuh or 12 mbtuh (mega) 1 cfm per square foot supply air. 1 ton cooling every 300-400 sq ft. It is okay to overestimate required air flow because systems have to be designed effectively rather than generic estimate that"s why you use trace. Trace: software program to calculate very precise amount of air needed. Compressor condenser expansion valve evaporator. 4 stages remain the same at any given system = a closed loop/cycle; meaning it doesn"t end. Add all sources of heat in space including. Amount of outside air required for a space based on the number of occupants. Exhaust air: air that you don"t recirculate; contaminated from lab, toilets, shower, janitor"s closet. Natural ventilation is a passive system; larger range in temperature and airflow, heating is often required if next to coastline.
